Otto in Africa
Otto the giant otterhound lives with his master in France. One day Duke, the owner of Otto, decides that Otto is too big to live in France and takes him to Africa. At a fort in Africa, Duke and Otto learn that Abou the Fierce and his bandits are planning an attack on the fort. Duke offers to fight them with only Otto to help.
The ending of Otto in Africa is rather funny. It is well worth your time to read this book. Otto is unfortunately out of print.